As a mid-career investigator in applied behavioral and social sciences related to HIV/AIDS, my goal in applying for a Short-term Mentored Career Development Award (K-18) is to learn to employ hierarchical linear modeling/structural equation modeling analytic strategies to more comprehensively address the complexity of the dyadic data sets generated by my collaborative research on HIV prevention with couples. These analytic skills would then enable me to assess the interactive effects of trauma, substance use, sexual partners and HIV on health behavior and health outcomes and apply those results at the individual, couple and population level. To meaningfully apply these data at the population level also require the ability to utilize and collaboratively develop statistical methods for translational studies and public health models. The research project, "Longitudinal Dyadic Analysis of HIV-positive Substance Users with a Trauma History" addresses the role of a potential third variable (substance use and sexual partners) on risk behavior outcomes in response to interventions among men and women as couples in which one member or both may be substance users and have a history of sexual trauma. This project seeks to clarify the relationship between the influence of sexual partners, substance use and sexual trauma on risk behaviors utilizing longitudinal dyadic analysis within the Actor Partner Interdependence Model framework (APIM). Specifically, I propose the following educational and research goals to: 1. Learn how to apply the APIM (theoretical model) for interpreting couples behavior and their response to interventions using the associated longitudinal dyadic statistical techniques (analytic component) to analyze existing data sets. Additionally, I propose to conduct analyses on a research project to using an existing R01: 2. Address the interactive effects of trauma, substance use, sexual partners and HIV on health behavior and health outcomes at the individual, couple and population level, utilizing longitudinal multiple groups the Actor Partner Interdependence Model framework (APIM) for indistinguishable dyads 3. Gain skills in the use and development of public health models and analytic strategies for translational studies. The APIM, which applies complex techniques of longitudinal structural equation modeling to the analysis of couple dyads in group formats, addressing the relative influences of partners and mediating factors on risk behaviors, will enable me to acquire the critical skills to interpret dyadic data and provide me with a bridge to develop dyadic translational research models and methods for couples interventions. Support through the K18 will provide protected time to gain competence in dyadic and public health statistical methods and models, while my research collaborations provide the remaining 50% time during the period of the award. PUBLIC HEALTH RELEVANCE: As a mid-career investigator in applied behavioral and social sciences related to HIV/AIDS, my goal in applying for a Short-term Mentored Career Development Award (K-18) is to learn to employ hierarchical linear modeling/structural equation modeling analytic strategies to more adequately address the complexity of the dyadic data sets generated by my research on HIV prevention with couples. These datasets address the interactive effects of trauma, substance use, sexual partners and HIV on health behavior and health outcomes at the individual, couple and population level.